During elections, what affects our decision to vote for one politician over another? We’d like to think that it’s an objective assessment of many different factors including their various policies, their values, their record and so on. But in reality, voters are just not that rational.

In the past, studies have shown that people can predict which of two politicians will win an election with reasonable accuracy based on a second-long looks at their faces. With a fleeting glance and little purposeful consideration, people make strong judgments about a candidate’s competence, that can sway their final choices. And they do this in a remarkably child-like way.

John Antonakis and Olaf Dalgas from the University of Lausanne found that when judging the faces of potential leaders, the decision-making technique of adults is no more sophisticated than that used by children.

They recruited 684 Swiss students and asked them to rate pairs of politicians who had run against each other in the 2002 French parliamentary elections. Based solely on black-and-white photos of the candidates, they had to say who was more competent and by what degree. There were 57 pairs in all, and each volunteer rated just one. All photos were official mug-shots, the researchers only used pairs of the same sex, and they excluded famous individuals such as Segolene Royal.

They found that the students’ competence judgments predicted the actual winners of the run-offs with a 72% accuracy. They even gave a good indication of the winner’s margin of victory – those who were deemed to “definitely” look more competent than their opponents were more likely to have beaten them by landslides.

It’s worth noting that this is a fairly conservative figure. Antonakis and Dalgas only used pairs of candidates where the loser was actually the incumbent and as they put it, “losers should not appear too incompetent given that they had previously won”.

In a second experiment, Antonakis and Dalgas showed that children judge faces in similar ways. At a university open day, they asked 681 children aged 5-13 and 160 adults to judge the same sets of faces. They had just sat through a computer game that simulated Odysseus’s journey from Troy to Ithaca, and required a certain amount of decision-making skill. Each participant was asked to imagine that they had to repeat the same trip and asked to pick one of the candidates to captain their boat.

The children’s choice of captain correctly predicted the winner of each parliamentary election with an accuracy of 72%, a remarkably similar figure to the score achieved by the adults in the first experiment. Indeed, when the judgments of the 160 adults were included in the analysis, the results didn’t change. The children were just as good at predicting election results as the grown-ups were; in fact, the child ratings in the second experiment strongly matched the adult ratings in the first one.

These results strongly suggest that adults and children are relying on the same aspects of facial appearance in order to judge a person’s competence, whichever those aspects might be. Despite their greater experience and (one would hope) more sophisticated reasoning skills, adults are no better at predicting election results than people many years their junior.

This study fits in nicely with several others, which suggest that election outcomes often rest on snap decisions. Alexander Todorov has repeatedly shown that people’s judgments of competence, based on split-second glances at photos, could predict the outcome of Senate elections or gubernatorial contests with an accuracy of around 70%.

The problem with that, of course, is that first impressions are not always accurate. For example, it’s actually very difficult to judge someone’s intelligence based on their appearance, while some people can give the impression of competence and have anything but. Plato pointed at similar tendencies in The Republic, in a passage that inspired Antonakis and Dalgas’s second experiment.

He asked readers to imagine “a ship in which there is a captain who is taller and stronger than any of the crew, but he is a little deaf and has a similar infirmity in sight, and his knowledge of navigation is not much better.” According to Plato, the crew is so deceived by appearances that they had failed to select a competent leader. So it was in his hypothetical scenario, so it often is in 21st century politics.

Now of course, you could argue that first impressions are merely that, and we are clearly capable of changing our opinions based on information we learn at a later date. Surely our views about political candidates must surely fluctuate as we learn more about their policies, affiliations, behaviour, character, and so on?

Well, that might be true, but it seems to be the exception rather than the rule. As Todorov’s work shows, voters have an unfortunate habit of anchoring themselves to their initial choices regardless of information that becomes available later in a campaign. And as I’ve written about before, even undecided voters tend to have already made up their minds, unbeknownst even to themselves.

Ideally, democracies should elect politicians on their actual competence, rather than simply the appearance of it. But as Antonakis and Dalgas say, “These findings suggest that voters are not appropriately weighting performance-based information on political candidates when undertaking one of democracy’s most important civic duties.”

Comments

Well, whoever said that humans were rational animals was way off. But now I start to wonder: how rational am I? I voted for Obama, and I thought it was because I agreed with his politics. But was it really? Maybe my mind made the same kind of snap decision and stuck with it.

Firstly, the judgments were made on competence, not attractiveness. Secondly, you would indeed expect that if asked to pick between two faces, you’d pick the one you prefer. But obviously, voting is meant to be about more than facial preferences – you would expect voting decisions to change as you discover more relevant information about the people concerned. So the interesting bit is the fact that the snap-judgments based on the faces are a reasonable predictor of actual election outcomes.

Given that 70% accuracy in a binary decision is not that much, and that the winner in an election is usually determined by a rather small percentage of the total voters; it would be interesting to see a calculation how large the effect of perceived competence on the individual voter’s decision probably is.

I did a short calculation, assuming a total 1000 voters deciding between two candidates. A percentage of p always chooses candidate A (the “competetent looking” one), the rest of the voters decides randomly whom to vote for. If p is 2%, then candidate A will already win with a probability of 70%.
Of course, the model I used is incredibly crude, but it shows that the data given above is not sufficient to support any claims about the rationality of the individual voter, as a really small percentage of voters can level a great influence.

As for the comment by Arno, 2% of 1000 is 20, right? If the rest vote randomly, we have 980 voters split equally between the two candidates, thus giving A 20 + 490 = 510. B gets 1000-510 = 490. Thus A and B are split 51-49%. With a chi-square value of .40, the differences is not significant between those proportions at conventional levels. How you get 70% for A. Could you explain your reasoning explicitly, showing your calculations?

With 20 voters always in favour of A, A needs atleast 481 votes from the remaining 980 voters to win. I plugged the numbers into a cumulated binomial distribution, which should yield a probability of about 70% for A to win.
You are right that the expected percentage of votes for A does not exceed that of B by great extent, but the actual numbers of votes are not relevant here, only which candidate will win.

Thanks Arno; however, you are making a big mistake here–we are not talking about voters but naive individuals whose data we use to predict voters’ choices. We are talking about statistical accuracy and not an absolute result.

Antonakis and Dalgas looked at predicting an election result from individual data. If you took a sample of naive raters, and using your logic, 510 would go for A and 490 for B. As I mentioned, the difference in terms of votes, using a chi-square test is not significant. Thus, using your logic, there is NO WAY a sample of individuals who are predicting a specific race would be able to do better than chance, which is what the chi-squared tests above shows. Thus, the Antonakis and Dalgas results are very impressive.

I am talking about voters, that probably explains the diverging results. My naive individuals always pick the better looking person A, thus A is the predicted winner. The question I am asking is to what extend one can infer about the voters from the accuracy of the prediction.

“72% prediction accuracy” among 57 pairs? That’s 41 right guesses and 16 wrong guesses. The chance a fair coin, tossed 57 times, comes up heads 16-or-fewer times, is 0.0632%.
So this result is significant at the 99.94% level.

This is horrible for humanity if your appearance is uncorrelated with your competence. But is it? Perhaps
humanity can survive because more-competent-looking people actually ARE more competent? I doubt it, but maybe.
So I suggest re-doing the experiment to find that out, using
fields in which competence can, in fact, be objectively judged. For example, do pairs of chessplayers with known
FIDE numerical chess ratings. How often can you tell from
their pictures, who has the higher rating?

I can tell you this: if I were asked to look at pictures of two people and asked to tell who’d finish first in a
10km footrace, or weightlifting competition, I bet I could achieve pretty damn good accuracy. So in some fields at least, predicting competence from appearance is quite possible.